Electro-optical device, electro-optical device manufacturing method, and electronic apparatus

ABSTRACT

Reflection layers are arranged for respective pixels with predetermined intervals in a row direction (X direction) and a column direction (Y direction) in a display region, and, subsequently to the display region, are arranged in the same manner with the predetermined intervals in the row direction (X direction) and the column direction (Y direction) also in a peripheral region around the display region. First electrodes, first light path adjusting layers, and second light path adjusting layers are arranged for the respective pixels in the display region, and are arranged so as to correspond to the respective reflection layers also in the peripheral region. The respective reflection layers are partially connected to each other in the peripheral region and are electrically connected to a second electrode at a cathode potential.

This application is a Continuation of application Ser. No. 15/423,155,filed on Feb. 2, 2017, and claims the benefits of Japanese PatentApplication No. 2016-026437, filed Feb. 15, 2016. The entire contents ofthe prior applications are hereby incorporated by reference herein intheir entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to an electro-optical device, anelectro-optical device manufacturing method, and an electronicapparatus.

2. Related Art

In recent years, an electro-optical device using organic light emittingdiodes (OLED) as light emitting elements has been used in an electronicapparatus capable of forming a virtual image, such as a head mountdisplay. As an example of the electro-optical device, as disclosed inJP-A-2015-62194, a device that includes reflection layers for respectivepixels and adjusts light paths based on optical distances between thereflection layers and pixel electrodes with cavity structures has beenproposed.

Furthermore, JP-A-2006-18085 discloses an electro-optical device inwhich pixels are arrayed in a display region displaying an image anddummy pixels that do not contribute to display of the image actually arearrayed in an adjacent region around the display region. The pixels inthe display region include light emitting elements in which lightemitting layers are interposed between anodes and cathodes. On the otherhand, no anode is formed in the dummy pixels in the adjacent region.

In the device having the configuration as disclosed in JP-A-2015-62194,a power supply line is used as the reflection layer in some cases. Insuch a case, defects on insulating films that are formed between thepower supply line as the reflection layer and the pixel electrodes maycause the power supply line and the pixel electrodes to beshort-circuited. For example, the defects on the insulating films tendto be generated on the boundary between the display region and theadjacent region around the display region.

In JP-A-2006-18085, the electrodes (anodes) configuring the lightemitting elements of the pixels in the display region are not providedin the dummy pixels in the adjacent region. This configuration causessteps corresponding to film thicknesses of the electrodes to begenerated between the display region and the adjacent region.Accordingly, uniformity of etching of insulating films is lowered andthe above-described defect can be generated in some cases. Furthermore,due to lowering in the uniformity of the etching of the insulatingfilms, the light path lengths are not stable and desired wavelengthscannot be obtained in the pixels in some cases.

SUMMARY

An advantage of some aspects of the embodiment is to provide anelectro-optical device capable of preventing a defect on insulatingfilms that are formed between reflection layers and pixel electrodesfrom being generated when the reflection layers are provided forrespective pixels, an electro-optical device manufacturing method, andan electronic apparatus including the electro-optical device.

An electro-optical device according to an aspect of the embodimentincludes first conductive layers in which light-reflective electrodesare arrayed in both of a display region and a peripheral region as aregion around the display region, second conductive layers in whichelectrodes are arrayed in both of the display region and the peripheralregion so as to overlap with the first conductive layers, a thirdconductive layer that is arranged so as to overlap with the secondconductive layers, insulating layers that are arranged between the firstconductive layers and the second conductive layers, and a light-emittingfunctional layer that is arranged between the second conductive layersand the third conductive layer. A portion of the first conductive layersarranged in the peripheral region are electrically connected to eachother with respective connection portions arranged in the same layer asthe first conductive layers, and a cathode potential or a groundpotential is applied to the first conductive layers arranged in theperipheral region.

With the aspect of the embodiment, the light-reflective first conductivelayers are arranged in both of the display region and the peripheralregion as the region around the display region. The second conductivelayers are arranged in both of the display region and the peripheralregion so as to overlap with the first conductive layers. Accordingly,the display region and the peripheral region have the same patterndensity and uniformity of etching of the insulating layers is improved.As a result, generation of defects on the insulating layers issuppressed. Furthermore, the cathode potential or the ground potentialis applied to the first conductive layers arranged in the peripheralregion. Therefore, even if the defects on the insulating layers aregenerated, the first conductive layers arranged in the peripheral regionhave the cathode potential or the ground potential and light emission ofpixels can thereby be suppressed.

In the electro-optical device according to the above-described aspect ofthe embodiment, a portion of the second conductive layers arranged inthe peripheral region may be electrically connected to the thirdconductive layer in at least a portion of the peripheral region in whichthe light-emitting functional layer is not formed, and the cathodepotential may be applied to a portion of the third conductive layer,which overlaps with the display region, and the third conductive layermay be electrically connected to the portion of the first conductivelayers arranged in the peripheral region. With the aspect of theembodiment, even if the defects on the insulating layers are generatedand the second conductive layers and the first conductive layers areelectrically connected to each other, both of the second conductivelayers and the third conductive layer have the cathode potential andlight emission of the pixels can thereby be suppressed.

The electro-optical device in the above-described aspect of theembodiment may further include a fourth conductive layer to which aground potential is applied, wherein the fourth conductive layer iselectrically connected to the portion of the first conductive layersarranged in the peripheral region. With the aspect of the embodiment,even if the defects on the insulating layers are generated and thesecond conductive layers and the first conductive layers areelectrically connected to each other, the second conductive layers havethe ground potential and light emission of the pixels can thereby besuppressed.

The electro-optical device in the above-described aspect of theembodiment may further include an etching stop layer between theinsulating layers and the first conductive layers, wherein the etchingstop layer overlaps with end portions of the insulating layers when seenfrom the above. With the aspect of the embodiment, the etching stoplayer overlaps with the end portions of the insulating layers when seenfrom the above. Therefore, even when another insulating layers arefurther laminated on the insulating layers, etching can be performedwithout influencing the first conductive layer under the etching stoplayer.

An electro-optical device manufacturing method according to anotheraspect of the embodiment includes arraying first conductive layers aslight-reflective electrodes in both of a display region and a peripheralregion as a region around the display region, forming insulating layerson the first conductive layers, arraying second conductive layers inboth of the display region and the peripheral region so as to overlapwith the first conductive layers, forming a light-emitting functionallayer on the second conductive layers, and forming a third conductivelayer so as to overlap with the second conductive layers. A portion ofthe first conductive layers arranged in the peripheral region areelectrically connected to each other with respective connection portionsarranged in the same layer as the first conductive layers, and areelectrically connected to a supply part of a cathode potential or aground potential.

With the aspect of the embodiment, the light-reflective first conductivelayers are arranged in both of the display region and the peripheralregion as the region around the display region. The second conductivelayers are arranged in both of the display region and the peripheralregion so as to overlap with the first conductive layers. Accordingly,the display region and the peripheral region have the same patterndensity and uniformity of etching of the insulating layers is improved.As a result, generation of defects on the insulating layers issuppressed. Furthermore, the cathode potential or the ground potentialis applied to the first conductive layers arranged in the peripheralregion. Therefore, even if the defects on the insulating layers aregenerated, the first conductive layers arranged in the peripheral regionhave the cathode potential or the ground potential and light emission ofpixels can thereby be suppressed.

An electronic apparatus according to still another aspect of theembodiment includes the electro-optical device in the above-describedaspect of the embodiment. The electronic apparatus providing high imagequality with stable light path lengths without pixel failure due toshort circuit of pixel electrodes can be provided with theelectro-optical device including light emitting elements such as OLEDs.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiment will be described with reference to the accompanyingdrawings, wherein like numbers reference like elements.

FIG. 1 is a plan view illustrating an electro-optical device accordingto an embodiment.

FIG. 2 is a circuit diagram of each display pixel located in a displayregion.

FIG. 3 is a plan view of a first region.

FIG. 4 is a partially broken plan view enlarging a region IV, Villustrated in FIG. 3.

FIG. 5 is a partially broken plan view excluding an etching stop layerfrom FIG. 4.

FIG. 6 is a cross-sectional view of pixels in the display region along arow direction.

FIG. 7 is a cross-sectional view of the pixels in the display regionalong a column direction.

FIG. 8 is a cross-sectional view of the pixels in the display regionalong the column direction.

FIG. 9 is a cross-sectional view of the pixels in the display regionalong the column direction.

FIG. 10 is a cross-sectional view of pixels in a peripheral region alongthe row direction.

FIG. 11 is a cross-sectional view of the pixels in the peripheral regionalong the column direction.

FIG. 12 is a cross-sectional view of the pixels in the peripheral regionalong the column direction.

FIG. 13 is a cross-sectional view of the pixels in the peripheral regionalong the column direction.

FIG. 14 is a descriptive view for explaining an example of an electronicapparatus.

FIG. 15 is a descriptive view for explaining another example of theelectronic apparatus.

FIG. 16 is a descriptive view for explaining still another example ofthe electronic apparatus.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

An embodiment will be described with reference to the drawings. Itshould be noted that in the following drawings, scales are madedifferent for respective layers and respective members in order to makethe layers and the members have sizes capable of being recognized in thedrawings.

FIG. 1 is a plan view illustrating an electro-optical device 1 accordingto an embodiment. The electro-optical device 1 in the embodiment is anorganic electroluminescence (EL) device in which light emitting elementsusing an organic EL material are formed on the surface of a substrate10. The substrate 10 is a plate-like member (semiconductor substrate)formed with a semiconductor material such as silicon and is used as abase member (base) on which the plurality of light emitting elements areformed. As illustrated in FIG. 1, the surface of the substrate 10 isdivided into a first region 12 and a second region 14. The first region12 is a rectangular region and the second region 14 is a rectangularframe-like region surrounding the first region 12.

In the first region 12, a plurality of scan lines 22 extending in a rowdirection (X direction), a plurality of control lines 24 extending inthe row direction (X direction) so as to correspond to the respectivescan lines 22, and a plurality of signal lines 26 extending in a columndirection (Y direction) intersecting with the row direction (Xdirection) are formed. Pixels P (PD, PE) are formed so as to correspondto respective intersections between the plurality of scan lines 22 andthe plurality of signal lines 26. Accordingly, the plurality of pixels Pare arrayed in a matrix form in the row direction (X direction) and thecolumn direction (Y direction).

A driving circuit 30, a plurality of mounting terminals 36, and a guardring 38 are installed in the second region 14. The driving circuit 30 isa circuit for driving the respective pixels P and is configured byincluding two scan line driving circuits 32 installed at positionsbetween which the first region 12 is interposed in the row direction (Xdirection) and a signal line driving circuit 34 installed in a regionextending in the row direction (X direction) in the second region 14.The plurality of mounting terminals 36 are formed in a region at theopposite side to the first region 12 with the signal line drivingcircuit 34 interposed therebetween and are electrically connected toexternal circuits (for example, an electronic circuit mounted on aflexible wiring substrate that is bonded to the substrate 10) such as acontrol circuit and a power supply circuit through the wiring substrate(not illustrated).

The plurality of electro-optical devices 1 in the embodiment arecollectively formed by cutting (scribing) a raw substrate having a sizecorresponding to a plurality of substrates 10. The guard ring 38 in FIG.1 prevents impact and static electricity at the time of cutting of theraw substrate from influencing the driving circuit 30 or the respectivepixels P and prevents water from entering from end surfaces (cutsurfaces of the raw substrate) of each substrate 10. As illustrated inFIG. 1, the guard ring 38 is formed in a ring shape (rectangularframe-like shape) surrounding the driving circuit 30, the plurality ofmounting terminals 36, and the first region 12.

The first region 12 in FIG. 1 is divided into a display region 16 and aperipheral region 18. The display region 16 is a region in which animage is displayed actually by driving of the respective pixels P. Theperipheral region 18 is a rectangular frame-like region surrounding thedisplay region 16 and pixels P (hereinafter, referred to as “dummypixels PD”) that do not contribute to display of the image actuallyalthough having similar structures to those of the respective pixels Pin the display region 16 are arranged in the peripheral region 18. Inthe following description, the pixels P in the display region 16 areexpressed as “display pixels PE” for the convenience in some cases inorder to clearly distinguish them from the dummy pixels PD in theperipheral region 18 in expression. The display pixels PE are elementsas minimum units of light emission.

FIG. 2 is a circuit diagram of each display pixel PE located in thedisplay region 16. As illustrated in FIG. 2, the display pixel PE isconfigured by including a light emitting element 45, a drivingtransistor TDR, a light emission control transistor TEL, a selectingtransistor TSL, and a capacitive element C. Although P-channeltransistors are employed for the respective transistors T (TDR, TEL, andTSL) of the display pixels PE in the embodiment, N-channel transistorscan also be used.

The light emitting element 45 is an electro-optical element in which alight-emitting functional layer 46 including a light emitting layerformed with an organic EL material is interposed between a firstelectrode (anode) E1 and a second electrode (cathode) E2. The firstelectrode E1 is individually formed for each display pixel PE and thesecond electrode E2 is continuous over a plurality of pixels P. As isunderstood from FIG. 2, the light emitting element 45 is arranged on apath connecting a first power supply conductor 41 and a second powersupply conductor 42 as a fourth conductive layer. The first power supplyconductor 41 is a power supply wiring to which a higher power supplypotential VEL is supplied and the second power supply conductor 42 is apower supply wiring to which a lower power supply potential (forexample, ground potential) VCT is supplied.

The driving transistor TDR and the light emission control transistor TELare arranged in series to the light emitting element 45 on the pathconnecting the first power supply conductor 41 and the second powersupply conductor 42. To be specific, one (source) of a pair of currentterminals of the driving transistor TDR is connected to the first powersupply conductor 41. The light emission control transistor TEL functionsas a switch controlling a conduction state (conduction/non-conduction)between the other (drain) of the pair of current terminals of thedriving transistor TDR and the first electrode E1 of the light emittingelement 45. The driving transistor TDR generates a driving currenthaving a current amount in accordance with a gate-source voltage ofitself. In a state in which the light emission control transistor TEL iscontrolled to be in an ON state, when the driving current is supplied tothe light emitting element 45 from the driving transistor TDR afterpassed through the light emission control transistor TEL, the lightemitting element 45 emits light with luminance in accordance with thecurrent amount of the driving current. In a state in which the lightemission control transistor TEL is controlled to be in an OFF state,supply of the driving current to the light emitting element 45 isblocked and the light emitting element 45 is turned OFF. A gate of thelight emission control transistor TEL is connected to the control line24.

The selecting transistor TSL in FIG. 2 functions as a switch controllinga conduction state (conduction/non-conduction) between the signal line26 and a gate of the driving transistor TDR. A gate of the selectingtransistor TSL is connected to the scan line 22. The capacitive elementC is an electrostatic capacitance in which a dielectric is interposedbetween a first electrode C1 and a second electrode C2. The firstelectrode C1 is connected to the gate of the driving transistor TDR andthe second electrode C2 is connected to the first power supply conductor41 (source of the driving transistor TDR). Accordingly, the capacitiveelement C holds the gate-source voltage of the driving transistor TDR.

The signal line driving circuit 34 supplies gradation potentials (datasignals) in accordance with gradations instructed for the respectivedisplay pixels PE by an image signal supplied from an external circuitto the plurality of signal lines 26 in parallel every writing period(horizontal scanning period). On the other hand, the scan line drivingcircuits 32 supply a scan signal to each scan line 22 to sequentiallyselect each of the plurality of scan lines 22 every writing period. Theselecting transistors TSL of the respective display pixels PEcorresponding to the scan line 22 selected by the scan line drivingcircuits 32 shift to be in ON states. Accordingly, the gradationpotentials are supplied to the gates of the driving transistors TDR ofthe respective display pixels PE after passed through the signal lines26 and the selecting transistors TSL and the capacitive elements C holdvoltages in accordance with the gradation potentials. On the other hand,when selection of the scan line 22 in the writing period is finished,the scan line driving circuits 32 supply a control signal to eachcontrol line 24 to control the light emission control transistors TEL ofthe respective display pixels PE corresponding to the control line 24 tobe in the ON states. Accordingly, driving currents in accordance withthe voltages held in the capacitive elements C in the last writingperiod are supplied to the light emitting elements 45 from the drivingtransistors TDR after passed through the light emission controltransistors TEL. When the respective light emitting elements 45 emitlight with luminance in accordance with the gradation potentials asdescribed above, any image instructed by the image signal is displayedon the display region 16.

The specific configuration of the electro-optical device 1 in theembodiment will be described in detail below. In the respective drawingsto be referred in the following description, dimensions and scales ofrespective elements are made different from those of the actualelectro-optical device 1 for the convenience of explanation.

FIG. 3 is a plan view of the first region 12. As is understood from FIG.3, the first region 12 is divided into the display region 16 and theperipheral region 18. As described above, the display pixels PE arearranged in the matrix form in the display region 16. An image isactually displayed in the display region 16 by driving of the respectivepixels PE. The dummy pixels PD that do not contribute to display of theimage actually although having the similar structures to those of therespective pixels PE are arranged in the peripheral region 18. FIG. 4and FIG. 5 are plan views enlarging a region IV, V illustrated in FIG. 3and omit a part thereof using breaking lines. FIG. 5 is a view excludingan etching stop layer from FIG. 4 for easiness of understanding.

FIG. 6 is a cross-sectional view corresponding to a cross sectionincluding line VI-VI in FIG. 4. FIG. 7 is a cross-sectional viewcorresponding to a cross section including line VII-VII in FIG. 4. FIG.8 is a cross-sectional view corresponding to a cross section includingline VIII-VIII in FIG. 4. FIG. 9 is a cross-sectional view correspondingto a cross section including line IX-IX in FIG. 4.

FIG. 10 is a cross-sectional view corresponding to a cross sectionincluding line X-X in FIG. 4. FIG. 11 is a cross-sectional viewcorresponding to a cross section including line XI-XI in FIG. 4. FIG. 12is a cross-sectional view corresponding to a cross section includingline XII-XII in FIG. 4. FIG. 13 is a cross-sectional view correspondingto a cross section including line XIII-XIII in FIG. 4.

The display pixels PE are composed of sub pixels of red (R), sub pixelsof green (G), and sub pixels of blue (B). As is understood from FIG. 4,in the display region 16, the sub pixels of red (R), the sub pixels ofgreen (G), and the sub pixels of blue (B) are repeatedly arranged inthis order with predetermined intervals along the row direction (Xdirection). The sub pixels of the same colors are arranged withpredetermined intervals along the column direction (Y direction). As isunderstood from FIG. 4, also in the peripheral region 18, the dummypixels PD corresponding to the above-described sub pixels are arrangedwith predetermined intervals along the row direction (X direction) andthe column direction (Y direction).

In FIG. 6 to FIG. 9 illustrating the configuration of theelectro-optical device 1 in the display region 16 and FIG. 10 to FIG. 13illustrating the configuration of the electro-optical device 1 in theperipheral region 18, lowermost layers are illustrated as insulatinglayers LD for the convenience. Although not illustrated in the drawings,the respective transistors T (TDR, TEL, and TSL) of the display pixelsPE are formed in layers under the insulating layers LD in the displayregion 16. To be specific, active regions (source/drain regions) of therespective transistors T (TDR, TEL, and TSL) of the display pixels PEare formed on the surface of the substrate 10 formed with thesemiconductor material such as silicon. Furthermore, transistors of thedummy pixels PD, which correspond to the respective transistors T (TDR,TEL, and TSL) of the display pixels PE, are formed in the peripheralregion 18.

Ions are injected into the active regions. Active layers of therespective transistors T (TDR, TEL, and TSL) of the display pixels PEand the dummy pixels PD are present between source regions and drainregions and ions of a type which is different from a type of the ions ofthe active regions are injected into the active layers.

The surface of the substrate 10 on which the active regions are formedare covered by gate insulating films and gates G (GDR, GEL, and GSL) ofthe respective transistors T are formed on the surfaces of theinsulating films. The gates G of the respective transistors T oppose theactive layers with the insulating films interposed therebetween.

On the surfaces of the insulating films on which the gates G of therespective transistors T are formed, a multilayered wiring layer formedby alternately laminating a plurality of insulating layers L (LA to LD)and a plurality of conductive layers (wiring layers) is formed. Therespective insulating layers L are formed with an insulating inorganicmaterial such as silicon compound (typically, silicon nitride or siliconoxide), for example. In the following description, a relation that aplurality of elements are collectively formed with the same process byselective removal of the conductive layer (single layer or a pluralityof layers) is expressed as “formed from the same layer”.

The first power supply conductor 41 and the second power supplyconductor 42 are formed in a layer above the layer in which the gates Gof the respective transistors T are formed. The first power supplyconductor 41 is formed in the display region 16 of the first region 12and the second power supply conductor 42 is formed in the peripheralregion 18 of the first region 12. The first power supply conductor 41and the second power supply conductor 42 are formed to be separated fromeach other and are electrically insulated from each other. The firstpower supply conductor 41 is conducted to the mounting terminal 36 towhich the higher power supply potential VEL is supplied through thewirings (not illustrated) in the multilayered wiring layer. In the samemanner, the second power supply conductor 42 is conducted to themounting terminal 36 to which the lower power supply potential VCT issupplied through the wirings (not illustrated) in the multilayeredwiring layer. The first power supply conductor 41 and the second powersupply conductor 42 in the embodiment are formed with a light-reflectiveconductive material containing silver and aluminum, for example, so asto have film thicknesses of approximately 100 nm.

The insulating layers LD as illustrated in FIG. 6 to FIG. 9 and FIG. 10to FIG. 13 are formed on the layers in which the first power supplyconductor 41 and the second power supply conductor 42 are formed. Asillustrated in FIG. 6 to FIG. 9, reflection layers 43 as firstconductive layers are formed on the surfaces of the insulating layers LDin the display region 16. The reflection layers 43 are formed with alight-reflective conductive material containing silver and aluminum, forexample. The reflection layers 43 are provided so as to extend in thecolumn direction (Y direction) for the respective sub pixels of blue(B), green (G), and red (R) and form rectangular regions when seen fromthe above, as illustrated in FIG. 4 and FIG. 5. The reflection layers 43are arranged with predetermined intervals in the row direction (Xdirection) and the column direction (Y direction).

As illustrated in FIG. 10 to FIG. 13, the reflection layers 43 as thefirst conductive layer are formed on the surfaces of the insulatinglayers LD also in the peripheral region 18 with the same process as thatin the display region 16. Accordingly, the reflection layers 43 in theperipheral region 18 are also formed with the light-reflectiveconductive material containing silver and aluminum, for example. Also inthe peripheral region 18, the reflection layers 43 are arranged withpredetermined intervals in the row direction (X direction) and thecolumn direction (Y direction) so as to correspond to the individualdummy pixels PE. Accordingly, as illustrated in FIG. 4 and FIG. 5,spaces 49 are formed between the adjacent reflection layers 43 in therow direction (X direction) as in the display region 16. Therefore,although not illustrated in the drawings, a cross-sectional viewcorresponding to a cross section including line A-A illustrated in FIG.4 and FIG. 5 is similar to that in FIG. 6 in the display region 16.

It should be noted that the reflection layers 43 are connected to eachother with no space therebetween in the column direction (Y direction)as indicated in a region R1 in FIG. 4. The state in which the reflectionlayers 43 are connected in the peripheral region 18 can be understoodfrom FIG. 10 to FIG. 13.

In the embodiment, the reflection layers 43 in the peripheral region 18are electrically connected to the second electrode E2 as a thirdconductive layer. That is to say, the reflection layers 43 in theperipheral region 18 are set to have the same potential as the cathodepotential.

As is understood from FIG. 6 and FIG. 10, reflection enhancing layers 50are formed on the reflection layers 43. The reflection enhancing layers50 are formed with silicon dioxide or the like, for example. Thereflection enhancing layers 50 have a higher refractive index than thereflection layers 43 formed with metal, thereby improving reflectioncharacteristics of the reflection layers 43.

As is understood from FIG. 6 to FIG. 9 and FIG. 10 to FIG. 13, a stopperlayer 44 as an etching stop layer is formed on the reflection enhancinglayers 50. The stopper layer 44 is formed with silicon nitride or thelike, for example. The stopper layer 44 is a layer that is formed forpreventing the layers in which the above-described transistors T areformed from being damaged at the time of etching when optical adjustmentlayers are formed. In FIG. 4, hatching which is the same as that for thestopper layer 44 illustrated in FIG. 6 to FIG. 9 and FIG. 10 to FIG. 13is added for the convenience.

The stopper layer 44 is formed so as to cover the reflection layers 43.Therefore, in the display region 16, as illustrated in FIG. 6 to FIG. 9,recesses are formed so as to correspond to the spaces between thereflection layers 43 adjacent in the row direction (X direction) and thecolumn direction (Y direction). The recesses are embedded with embeddingoxide layers 51, as illustrated in FIG. 6 to FIG. 9. The embedding oxidelayers 51 are formed with silicon dioxide or the like, for example.

The recesses as formed in the display region 16 are not formed on thestopper layers 44 at positions corresponding to the portions in whichthe reflection layers 43 are connected in the peripheral region 18, asillustrated in FIG. 10 to FIG. 13. However, recesses are formed in theportions including line A-A illustrated in FIG. 4 as in the displayregion 16 and are embedded with the embedding oxide layers 51.

As illustrated in FIG. 4 to FIG. 9, relay electrodes QD are formed onthe surfaces of the stopper layer 44 and the embedding oxide layers 51.The relay electrodes QD are wirings that are connected to the lightemission control transistors TEL. The relay electrodes QD are formed inthe display region 16 and the peripheral region 18. The relay electrodesQD are formed with a light-shielding conductive material (for example,titanium nitride), for example.

As illustrated in FIG. 6 to FIG. 9 and FIG. 10 to FIG. 13, first lightpath adjusting layers 60 a as island-like insulating layers are formedon the surfaces of the stopper layer 44, the embedding oxide layers 51,and the relay electrodes QD. Second light path adjusting layers 60 b asisland-like insulating layers are formed on the surfaces of the firstlight path adjusting layers 60 a in the sub pixels of red (R). The firstlight path adjusting layers 60 a and the second light path adjustinglayers 60 b are light-transmitting film members defining resonancewavelengths (that is, display colors) of resonance structures of therespective display pixels PE. The first light path adjusting layers 60 aand the second light path adjusting layers 60 b are formed with silicondioxide or the like, for example. Details of the resonance structures ofthe respective display pixels PE, the first light path adjusting layers60 a, and the second light path adjusting layers 60 b will be describedlater.

As illustrated in FIG. 6 to FIG. 9 and FIG. 10 to FIG. 13, the firstelectrodes E1 as second conductive layers are formed on the surfaces ofthe first light path adjusting layers 60 a or the second light pathadjusting layers 60 b for the respective display pixels PE in thedisplay region 16. Furthermore, the first electrodes E1 are formed forthe respective dummy pixels PD in the peripheral region 18. The firstelectrodes E1 are formed with a light-transmitting conductive materialsuch as indium tin oxide (ITO), for example. The first electrodes E1 aresubstantially rectangular electrodes (pixel electrodes) functioning asthe anodes of the light emitting elements 45, as described above withreference to FIG. 2. The first electrodes E1 make contact with the relayelectrodes QD via through-holes HE, as illustrated in FIG. 4 to FIG. 9and FIG. 10 to FIG. 13. That is to say, the first electrodes E1 areconducted to the active regions (drains) of the light emission controltransistors TEL via a plurality of relay electrodes (not illustrated) inaddition to the relay electrodes QD.

As illustrated in FIG. 6 to FIG. 9 and FIG. 10 to FIG. 13, a pixeldefining layer 65 is formed on the surfaces of the first light pathadjusting layers 60 a or the second light path adjusting layers 60 b onwhich the first electrodes E1 are formed over the entire area of thesubstrate 10. The pixel defining layer 65 is formed with an insulatinginorganic material such as silicon compound (typically, silicon nitrideor silicon oxide), for example. Although not illustrated in thedrawings, openings corresponding to the respective first electrodes E1in the display region 16 and the peripheral region 18 are formed in thepixel defining layer 65. Regions of the pixel defining layer 65 in thevicinity of inner peripheral edges of the openings overlap withperipheral edges of the first electrodes E1. That is to say, the innerperipheral edges of the openings are located at the inner side of theperipheral edges of the first electrodes E1 when seen from the above. Asis understood from the above description, the pixel defining layer 65 isformed in a grid form when seen from the above.

The light-emitting functional layer 46 is formed on the surfaces of thefirst light path adjusting layers 60 a or the second light pathadjusting layers 60 b on which the first electrodes E1 and the pixeldefining layer 65 are formed. The light-emitting functional layer isformed in the display region 16 of the first region 12 and is continuousover the plurality of display pixels PE. On the other hand, thelight-emitting functional layer is not formed in the peripheral region18 and the second region 14. The light-emitting functional layerincludes the light emitting layer formed with the organic EL materialand emits white light upon supply of electric current. It should benoted that the light-emitting functional layer 46 can also include atransport layer or an injection layer of electrons and holes which aresupplied to the light emitting layer.

The second electrode E2 as the third conductive layer is formed on thesurfaces of the first light path adjusting layers 60 a or the secondlight path adjusting layers 60 b on which the light-emitting functionallayer is formed over the entire area of the first region 12 (the displayregion 16 and the peripheral region 18). The second electrode E2functions as the cathodes of the light emitting elements 45 as describedabove with reference to FIG. 2. Regions (light emitting regions) of thelight-emitting functional layer, which are interposed between the firstelectrodes E1 and the second electrode E2, at the inner side of therespective openings in the pixel defining layer 65 emit light. That isto say, portions in which the first electrodes E1, the light-emittingfunctional layer, and the second electrode E2 are laminated at the innerside of the openings function as the light emitting elements 45. As isunderstood from the above description, the pixel defining layer 65defines planar shapes and the sizes (regions emitting light actually) ofthe light emitting elements 45 for the respective display pixels PE. Theelectro-optical device 1 in the embodiment is a micro display in whichthe light emitting elements 45 are arranged with extremely highdefinition. For example, an area (area of one opening) of one lightemitting element 45 is set to be equal to or smaller than 40 μm² and aninterval between the light emitting elements 45 that are adjacent toeach other in the X direction is set to be equal to or larger than 0.5μm and equal to or smaller than 2.0 μm.

Portions of the second electrode E2 over the entire area of the firstregion 12, which are located in the peripheral region 18, areelectrically connected to the above-described reflection layers 43 inthe peripheral region 18 because the light-emitting functional layer isnot formed in the peripheral region 18 as described above. As isunderstood from the above description, the second electrode E2 formedover both of the display region 16 and the peripheral region 18 isconducted to the second power supply conductor 42 as the fourthconductive layer through the reflection layers 43 in the peripheralregion 18. That is to say, the lower power supply potential VCT issupplied to the second electrode E2 through the reflection layers 43from the second power supply conductor 42. Although the light-emittingfunctional layer is formed in a part of the peripheral region 18 in somecases depending on conditions at the time of formation of thelight-emitting functional layer, the second electrode E2 is electricallyconnected to the reflection layers 43 as long as the first electrodes E1are exposed in another part of the peripheral region 18.

The second electrode E2 functions as a semi-transmitting reflectionlayer having property (semi-transmitting reflectivity) of transmitting apart of light which has reached the surface thereof and reflectingremaining part of the light. For example, the semi-transmittingreflective second electrode E2 is formed by forming a light-reflectiveconductive material such as alloy containing silver and magnesium into asufficiently thin film thickness. Emitted light from the light-emittingfunctional layer reciprocates between the reflection layers 43 and thesecond electrode E2, a component thereof having a specific resonancewavelength is selectively amplified, and then, the light passes throughthe second electrode E2 and is output to the observation side (oppositeside to the substrate 10). That is to say, the resonance structuresresonating the output light from the light-emitting functional layer areformed between the reflection layers 43 and the second electrode E2functioning as the semi-transmitting reflection layer. The first lightpath adjusting layers 60 a and the second light path adjusting layers 60b are elements for individually setting the resonance wavelengths(display colors) of the resonance structures for the respective displaycolors of the display pixels PE. To be specific, the resonancewavelengths of the output light on the respective display pixels PE areset for the respective display colors by appropriately adjusting lightpath lengths (optical distances) between the first power supplyconductor 41 and the second electrode E2 configuring the resonancestructures in accordance with the film thicknesses of the first lightpath adjusting layers 60 a and the second light path adjusting layers 60b.

The first light path adjusting layers 60 a and the second light pathadjusting layers 60 b are formed with a light-transmitting insulatingmaterial such as silicon compound (typically, silicon nitride or siliconoxide). The first light path adjusting layers 60 a are formed withsilicon nitride, for example, so as to have the film thickness of equalto or larger than 40 nm and equal to or smaller than 100 nm and thesecond light path adjusting layers 60 b are formed with silicon oxide,for example, so as to have the film thickness of equal to or larger than40 nm and equal to or smaller than 100 nm.

The first light path adjusting layers 60 a and the second light pathadjusting layers 60 b are selectively removed by etching in accordancewith the display colors of the respective display pixels PE. To bespecific, in the display pixels PE of blue, the first light pathadjusting layers 60 a and the second light path adjusting layers 60 bare removed. In the display pixels PE of green, the second light pathadjusting layers 60 b are removed and the light paths are adjusted bythe first light path adjusting layers 60 a. In the display pixels PE ofred, the light paths are adjusted by lamination of the first light pathadjusting layers 60 a and the second light path adjusting layers 60 b.

Although the display region 16 has been focused in the abovedescription, the first light path adjusting layers 60 a and the secondlight path adjusting layers 60 b having the same configurations as thosein the display region 16 are formed also in the dummy pixels PD in theperipheral region 18.

Although not illustrated in the drawings, a sealing member is formed onthe surface of the second electrode E2 over the entire area of thesubstrate 10. The sealing member is a light-transmitting film memberpreventing entrance of the outside air and water by sealing therespective elements formed on the substrate 10. The respective mountingterminals 36 in FIG. 1 are exposed to the outside through openingsformed in regions of the sealing member, which are connected to theflexible wiring substrate.

The sealing member is formed on the surface of the second electrode E2and makes direct contact with the surface of the second electrode E2.The sealing member is formed with an insulating inorganic material suchas silicon compound (typically, silicon nitride or silicon oxide), forexample, so as to have a film thickness of approximately 200 nm to 400nm, for example. A high-density plasma film formation technique such asa plasma chemical vapor deposition (CVD) method, an electron cyclotronresonance (ECR) plasma sputtering method, and an ion plating method ispreferably used for formation of the sealing member. A sealing memberformed with silicon oxynitride can also be formed by depositing siliconoxide in a nitrogen atmosphere. Furthermore, inorganic oxidesrepresented by metal oxides such as titanium oxide can also be used as amaterial of the sealing member.

As described above, in the embodiment, not only the display pixels PEare arranged in the display region 16 but also the dummy pixels PDhaving the same structures as those of the display pixels PE arearranged in the peripheral region 18. Furthermore, the display pixels PEand the dummy pixels PD are arranged with the predetermined intervals inthe row direction (X direction) and the column direction (Y direction).In particular, the reflection layers 43 are arranged for the respectivedisplay pixels PE in the display region 16 with the predeterminedintervals in the row direction (X direction) and the column direction (Ydirection). Furthermore, also in the peripheral region 18, thereflection layers 43 are arranged with the intervals that are the sameas the predetermined intervals in the display region 16 in the rowdirection (X direction) and the column direction (Y direction),subsequently to the display region 16. The first electrodes E1, and thefirst light path adjusting layers 60 a and the second light pathadjusting layers 60 b as the insulting layers are arranged for therespective display pixels PE in the display region 16. In addition, thefirst electrodes E1, and the first light path adjusting layers 60 a andthe second light path adjusting layers 60 b are arranged also in theperipheral region 18 so as to correspond to the respective reflectionlayers 43. The electro-optical device 1 is configured as described abovein the embodiment and the display region 16 and the peripheral region 18therefore have the same pattern density. As a result, uniformity ofetching is improved when the reflection enhancing layers 50 and thestopper layer 44 are formed on the reflection layers 43, and the firstlight path adjusting layers 60 a and the second light path adjustinglayers 60 b are further formed thereon. Accordingly, defects on thefirst light path adjusting layers 60 a and the second light pathadjusting layers 60 b are difficult to be generated in the vicinity ofthe boundary between the display region 16 and the peripheral region 18,thereby suppressing generation of failures such as short circuit betweenthe first electrodes E1 and another conductive layer.

Furthermore, in the peripheral region 18, the respective reflectancelayers 43 arranged for the respective dummy pixels PD are partiallyconnected to each other as indicated in the region R1 in FIG. 4 and areelectrically connected to the second electrode E2 having the cathodepotential. That is to say, the potentials of the reflectance layers 43in the peripheral region 18 are equal to the cathode potential.Therefore, even if the defects on the first light path adjusting layers60 a and the second light path adjusting layers 60 b are generated andthe first electrodes E1 in the display region 16 and the reflectancelayers 43 in the peripheral region 18 are short-circuited, the firstelectrodes E1 have the cathode potential. This can prevent failures suchas erroneous light emission of the pixels with the short-circuited firstelectrode E1.

Moreover, in the embodiment, the stopper layer 44 is arranged betweenthe first light path adjusting layers 60 a and the second light pathadjusting layers 60 b as the insulating layers and the reflection layers43. The end portions of the first light path adjusting layers 60 a andthe second light path adjusting layers 60 b in the respective displaypixels PE are located on the stopper layer 44 when seen from the aboveas is understood from FIG. 6 to FIG. 9. Accordingly, etching of thefirst light path adjusting layers 60 a and the second light pathadjusting layers 60 b is performed on the flattened surface of thestopper layer 44, thereby improving uniformity of the etching. As aresult, generation of the defects on the first light path adjustinglayers 60 a and the second light path adjusting layers 60 b can besuppressed.

Variations

The invention is not limited to the above-described embodiments and, forexample, the following various variations can be made. Furthermore, itis needless to say that the embodiments and variations can beappropriately combined.

(1) In the above-described embodiment, the reflection layers 43 in theperipheral region 18 are electrically connected to the second electrodeE2. The embodiment is however not limited to the configuration and thesecond electrode E2 in the peripheral region 18 may be electricallyisolated from the display region 16 and the reflection layers 43 in theperipheral region 18 may be electrically connected to the second powersupply conductor 42 as the power supply wiring having the groundpotential.

(2) In the above-described embodiment, the reflection layers and theopenings in the sub pixels of the display pixels PE and the dummy pixelsPD are provided so as to extend in the column direction (Y direction)and the plurality of sub pixels are arranged with the common intervalsin the column direction (Y direction). In addition, the reflectionlayers and the openings in the respective pixels are arranged with thecommon intervals also in the row direction (X direction). The embodimentis however not limited to the configuration and the reflection layersand the openings in the sub pixels of the display pixels PE and thedummy pixels PD may be provided so as to extend in the row direction (Xdirection) and the reflection layers and the openings may be arrangedwith common intervals in the column direction (Y direction).Furthermore, the reflection layers and the openings in the sub pixels ofthe respective colors are arrayed such that the widths thereof in therow direction (X direction) are equal to each other. The embodiment ishowever not limited to the configuration. For example, the followingconfiguration may be employed. That is, the reflecting portions and theopenings in the sub pixels of blue are made to extend in the columndirection (Y direction) as illustrated in FIG. 4 such that the lengthsthereof in the column direction (Y direction) are maximum. The lengthsof the reflecting portions and the openings in the sub pixels of red andthe reflecting portions and the openings in the sub pixels of green inthe column direction (Y direction) are set to the half of the lengths ofthose in the sub pixels of blue. Under this conditions, the reflectingportions and the openings in the sub pixels of red and the reflectingportions and the openings in the sub pixels of green are arranged sideby side in the column direction (Y direction). Alternatively, thefollowing configuration may be employed. That is, the reflectingportions and the openings in the sub pixels of blue are made to extendin the row direction (X direction) such that the widths thereof in therow direction (X direction) are maximum. The widths of the reflectingportions and the openings in the sub pixels of red and the reflectingportions and the openings in the sub pixels of green in the rowdirection (X direction) are set to the half of the widths of those inthe sub pixels of blue. Under this conditions, the reflecting portionsand the openings in the sub pixels of red and the reflecting portionsand the openings in the sub pixels of green are arranged side by side inthe row direction (X direction).

(3) Although the OLED is employed as an example of the electro-opticalmaterial in the above-described embodiment, the embodiment is alsoapplied to electro-optical devices using electro-optical materials otherthan the OLED. The electro-optical material is a material that ischanged in the optical characteristics such as transmittance andluminance upon supply of an electric signal (current signal or voltagesignal). For example, the embodiment can also be applied to a displaypanel using a light emitting element such as liquid crystal, inorganicEL, and light emitting polymer in the same manner as the above-describedembodiment. Furthermore, the embodiment can also be applied to anelectrophoretic display panel using microcapsules containing coloredliquid and white particles dispersed in the liquid as theelectro-optical material in the same manner as the above-describedembodiment. Moreover, the embodiment can also be applied to a twist balldisplay panel using twist balls painted with different colors forregions having different polarities as the electro-optical material inthe same manner as the above-described embodiment. The embodiment canalso be applied to various electro-optical devices such as a tonerdisplay panel using black toner as the electro-optical material and aplasma display panel using high-pressure gas such as helium and neon asthe electro-optical material in the same manner as the above-describedembodiment.

Applications

The embodiment can be utilized for various types of electronicapparatuses. FIG. 14 to FIG. 16 illustrate specific forms of theelectronic apparatuses as application targets of the embodiment.

FIG. 14 is a perspective view illustrating outer appearance of a headmount display as the electronic apparatus employing the electro-opticaldevice of the embodiment. As illustrated in FIG. 14, a head mountdisplay 300 includes temples 310, a bridge 320, and projection opticalsystems 301L and 301R like common glasses when seen from the outside.Although not illustrated in the drawing, the electro-optical device 1for the left eye and the electro-optical device 1 for the right eye areprovided in the vicinity of the bridge 320 at the back sides of theprojection optical systems 301L and 301R.

FIG. 15 is a perspective view of a portable personal computer employingthe electro-optical device. A personal computer 2000 includes theelectro-optical device 1 displaying various types of images and a mainbody portion 2010 on which a power supply switch 2001 and a keyboard2002 are installed.

FIG. 16 is a perspective view of a mobile phone. A mobile phone 3000includes a plurality of operation buttons 3001 and scroll buttons 3002,and the electro-optical device 1 displaying various types of images. Ascreen displayed on the electro-optical device 1 is scrolled byoperating the scroll buttons 3002. The embodiment can also be applied tothe mobile phone like this.

Examples of the electronic apparatus to which the embodiment can beapplied include, in addition to the apparatuses as illustrated in FIG.14 to FIG. 16, personal digital assistants (PDA). Other examples thereofinclude digital still cameras, televisions, video cameras, carnavigation systems, on-vehicle displays (instrument panels), electronicnotebooks, electronic paper, calculators, word processors, workstations,video phones, and POS terminals. Furthermore, the embodiment can beapplied to printers, scanners, copying machines, video players, andapparatuses including touch panels, and the like.

The entire disclosure of Japanese Patent Application No. 2016-026437,filed Feb. 15, 2016 is expressly incorporated by reference herein.

What is claimed is:
 1. An electro-optical device comprising: a firstconductive layer that is provided in a display region; a secondconductive layer that is provided in the same layer as the firstconductive layer and in a peripheral region as a region around thedisplay region; a third conductive layer that is provided in the displayregion so as to overlap with the first conductive layer; a fourthconductive layer that is provided in the same layer as the thirdconductive layer and in the peripheral region so as to overlap with thesecond conductive layer; a fifth conductive layer that is provided inthe display region so as to overlap with the third conductive layers; asixth conductive layer that is provided in the same layer as the fifthconductive layer and in the peripheral region so as to overlap with thefourth conductive layers; a first insulating layer that is arrangedbetween the first conductive layer and the third conductive layer; asecond conductive layer that is arranged between the second conductivelayer and the fourth conductive layer; and a light-emitting functionallayer that is arranged between the third conductive layer and the fifthconductive layer, wherein the first conductive layer and the secondconductive layer are formed with a light-reflective conductive materialand are electrically connected with each other.
 2. The electro-opticaldevice according to claim 1, wherein the second conductive layer issupplied a cathode potential or a ground potential.
 3. Theelectro-optical device according to claim 1, wherein the fifthconductive layer and the sixth conductive layer are electricallyconnected with each other, the fourth conductive layer and the sixthconductive layer are electrically connected with each other, and thesecond conductive layer and the fourth conductive layer are electricallyconnected with each other.
 4. The electro-optical device according toclaim 3, wherein the second conductive layer is supplied a cathodepotential or a ground potential.
 5. The electro-optical device accordingto claim 1, including an etching stop layer between the first insulatinglayer and the first conductive layer and between the second insulatinglayer and the second conductive layer, wherein the etching stop layeroverlaps with end portions of the insulating layers when seen from theabove.
 6. An electronic apparatus comprising the electro-optical deviceaccording to claim
 1. 7. An electronic apparatus comprising theelectro-optical device according to claim
 2. 8. An electronic apparatuscomprising the electro-optical device according to claim
 3. 9. Anelectronic apparatus comprising the electro-optical device according toclaim
 4. 10. An electronic apparatus comprising the electro-opticaldevice according to claim 5.